Dental handpiece construction



M y 1966 J. v. BORDEN 3,252,719 v DENTAL HANDPIECE CONSTRUCTION OriginalFiled July 28, 1959 IN VENTOR JOHN 1! 50/205 N Mm 9 m ATTORNEYS- UnitedStates Patent 2 Claims. c1. 2ss 137 This is a division of applicationSerial No. 830,101, filed July 28, 1959, now Patent No. 3,061,930.

This invention relates generally to the construction of a dentalhandpiece, and particularly to a construction of a handpiece of thefluid turbine, high-speed type, which requires cooling and lubricatingmeans in the vicinity of the driven bur.

High speed drills developed in recent years have become quite complexand sophisticated with each additional improvement. This complexity,coupled with the high intensity of the Vibrations transmitted from therotating elements, has caused looseness and damage to various connectingpoints of the handpiece. The fluids for cooling, and the fluids fordriving the turbine, are most conveniently delivered to this point ofuse interiorly of the dental handpiece handle. This adds to the alreadyexisting complexities and production difficulties. It is therefore anobjective of this invention to provide an improved neck portionconstruction for a dental handpiece.

It is a further objective of the invention to provide for a handpiece, asubstantially solid neck portion upon which various conventional machineoperations have been performed, such that the neck portion may achieveits connection purposes and all or any of the fluid delivery missionsassigned to it.

Further objectives and advantages of this invention will be apparentfrom the following description and claims wherein the construction,arrangement and cooperation of the several parts of the instrument areset forth.

In the drawings:

FIG. 1 is a cross-sectional view of a dental handpiece having portionsof the interior of the handpiece in elevation;

FIG. 2 is a perspective view of a portion of the neck portion of thehandpiece shown in FIG. 1;

FIG. 3 is an end view of the neck portion before attachment to theturbine housing;

FIG. 4 is a view along the line 33 in FIG. 1;

FIG. 5 is a view along the line 44 in FIG. 1; and

FIG. 6 is a perspective view of a different neck portion showing thevariety of missions the structure of this invention may accomplish.

Referring now to the drawings in which like numerals indicate likeparts, the numeral 10 designates one form of the handpiece of thisinvention. The handpiece is comprised, generally, of a turbine housing12, a neck portion 14, sleeve 16, and a hollow handle 18.

This invention relates primarily to the novel manner in which the neckportion and sleeve connect the turbine housing to the handle.

The cylindrical housing 12 encloses an air turbine assembly 24 rotatablymounted by ball bearings 26 and 28. The bur-receiving end of the housinghas means therein to produce an air and water spray and direct it to thevicinity of the bur head. The specific means for accomplishing thisspray is not included as a part of this invention, but may, forinstance, be of the type covered by my co-pending application Serial No.813,092.

The particular air turbine assembly disclosed by FIG. 1 is of the typewhich receives a jet of air near the midsection of its rotor blades andexhausts the air at its upper and lower ends. Portions of this air areexhausted through the bearings and the remainder through the end of thehandpiece. For these purposes the housing 12 has an air inlet opening32, and two exhaust openings 32 and 36 formed therein.

In the past there has been some difliculty encountered in aligning andsecurely fastening the handle to the housing so that the proper deliveryand exhaust ports in the handle would match the proper fluid deliveryconduits in the handle. This fastening pointis right at the point Wherethe housing vibrations are transmitted to the handle and the resultingconnection must be strong. This invention provides a neck portion 14formed of a solid piece of material upon which various operations havebeen performed. The neck portion comprises a reduced portion 38 formedat one end thereof and upper and lower flats 40 and 42 which have beenmilled on the reduced portion. Rearwardly spaced from lower flat 42 is atransverse slot 44. Centrally drilled in neck portion 14 is the airinlet passage 46 which has a reduced portion 47 adapted to be incommunication with orifice 32 of the housing 12. An air exhaust channel48 is drilled between flats 40 and 42 offset from passage 46. Extendingrearwardly from said exhaust channel is an air exhaust artery 50 whichextends rearwardly through said neck portion to connect with a hose 52,or into the interior of the handle and is subsequently exhausted throughthe end of the handpiece.

Also drilled in the neck portion, and in communication with thetransverse slot 44, is the water inlet passage 54 which extendsrearwardly through the neck portion and is connected to water pipe 56.Extending into slot 44 from the other direction is water direction tube58 which directs water to a point 60 where the air and water form aspray. In FIG. 1 it can be seen that tube 58 extends well within chamber44 an amount 59. This extension operates somewhat as a screening meanswhich aids in preventing foreign materials in the water from enteringtube 58. These milling operations are conveniently accomplished whilethe neck 14 is longitudinally straight. The neck piece is then bent intothe contra-angle shape if desired.

After the relatively simple mechanical operations of lathing reducedsection 38, milling recesses 40 and 42, and slot 44, and drilling airexhaust channel 48, a cylindrical sleeve 60 is snugly fitted over thesesurface configurations and the required chambers are formed. It is asimple matter to then align the correct chambers with the properorifices in housing 12. There is an opening 62 in the sleeve 60 so thatwater directing tube 58 may enter the chamber formed by slot 44.

The neck portion is soldered or otherwise connected to the housing 12.It can be seen that the structure shown presents a relatively solidmember at the point of attachment between the housing and neck piece.There are no normally weak tubular and conduit connections which arelikely to shake loose when the structure of this invention is used.

The invention is not limited to the type grooves and chambers shown anddescribed. For instance, FIG. 6 shows a neck portion 70 having dual airsupply apertures 72 and 74 in the event the particular turbine usedmight be of the twin turbine type. The portion 70 also shows a sidechamber 76 in the event a side exhaust is to be used. This demonstrateshow the neck portion is adaptable to be used with handpieces requiring avariety of functions to be performed. If, for instance, there was not tobe any water cooling with a particular handpiece, the water deliveryslots and apertures would not have to be machined in the neck piece.

In a general manner, while I have, in the above description, disclosedwhat I deem to be practical and 3 efiicient embodiments of my invention,it should be well understood that I do not wish to be limited thereto,as there might be changes made in the arrangement, disposition and formof the pants without departing from the principle of the presentinvention as comprehended 5 within the scope of the accompanying claims.

I claim:

1. A coupling composed of two separable subassemblies, one of saidsub-assemblies being in communication with a closed chamber, the otherof said sub-assemblies being in communication with a supply of fluid,each of said subassemblies being provided with three conduit means, eachconduit means of one sub-assembly being in separate communication with aconduit means of the other sub-assembly, one of said sub-assembliesbeing provided with a tubular sleeve portion, the other of saidsubassemblies being provided with a projecting portion fitted withinsaid sleeve portion, said projecting portion being provided with a pairof flat peripheral sections forming a pair of chambers with said sleeve,passage means for 20 communication between said pair of chambers, one ofthe conduit means of each sub-assembly terminating in mating aperturesprovided in respective abutting radial wall portions of each of saidsub-assemblies in separable communication with one other, each of theremaining conduit means of each sub-assembly terminating incommunication respectively with one of the chambers formed by the sleeveand the pair of flat sections, one of the remaining conduits of theother sub-assembly terminating in communication with said passage means.

2. The invention as defined in claim 1, wherein an additional flat isprovided on said projecting portion to provide a third separate chamber.

References Cited by the Examiner UNITED STATES PATENTS 1,454,996 5/1923Erret t 285l37 2,667,302 1/1954 Schmitz 285l3l 2,838,029 6/1958 Bettoni285l33 FOREIGN PATENTS 579,447 7/ 1958 Italy.

CARL W. TOMLIN, Primary Examiner.

S. R. MILLER, Assistant Examiner.

1. A COUPLING COMPOSED OF TWO SEPARABLE SUBASSEMBLIES, ONE OF SAIDSUB-ASSEMBLIES BEING IN COMMUNICATION WITH A CLOSED CHAMBER, THE OTHEROF SAID SUB-ASSEMBLIES BEING IN COMMUNICATION WITH A SUPPLY OF FLUID,EACH OF SAID SUBASSEMBLIES BEING PROVIDED WITH THREE CONDUIT MEANS, EACHCONDUIT MEANS OF ONE SUB-ASSEMBLY BEING IN SEPARATE COMMUNICATION WITH ACONDUIT MEANS OF THE OTHER SUB-ASSEMBLY, ONE OF SAID SUB-ASSEMBLIESBEING PROVIDED WITH A TUBULAR SLEEVE PORTION, THE OTHER OF SAIDSUBASSEMBLIES BEING PROVIDED WITH A PROJECTING PORTION FITTED WITHINSAID SLEEVE PORTION, SAID PROJECTING PORTION BEING PROVIDED WITH A PAIROF FLAT PERIPHERAL SECTIONS FORMING A PAIR OF CHAMBERS WITH SAID SLEEVE,PASSAGE MEANS FOR COMMUNICATION BETWEEN SAID PAIR OF CHAMBERS, ONE OFTHE CONDUIT MEANS OF EACH SUB-ASSEMBLY TERMINATING IN MATING APERTURESPROVIDED IN RESPECTIVE ABUTTING RADIAL WALL PORTIONS OF EACH OF SAIDSUB-ASSEMBLIES IN SEPARABLE COMMUNICATION WITH ONE OTHER, EACH OF THEREMAINING CONDUIT MEANS OF EACH SUB-ASSEMBLY TERMINATING INCOMMUNICATION RESPECTIVELY WITH ONE OF THE CHAMBERS FORMED BY THE SLEEVEAND THE PAIR OF FLAT SECTIONS, ONE OF THE REMAINING CONDUITS OF THEOTHER SUB-ASSEMBLY TERMINATES IN COMMUNICATION WITH SAID PASSAGE MEANS.